What is the difference between 4G, 5G and Wi-Fi calling?
4G and 5G are mobile network generations. Wi-Fi calling is a feature letting your phone route calls over an internet connection instead of the mobile network.
4G (LTE). The generation that made mobile data genuinely usable, delivering typical real-world speeds of tens of megabits. Voice over 4G — VoLTE — carries calls as data rather than over the older circuit-switched network, which gives faster call setup and better audio quality through wideband codecs.
5G. The current generation, and it comes in two substantially different forms that marketing rarely distinguishes:
Sub-6GHz — the version most people actually get. Better capacity and moderately higher speeds than 4G, with similar coverage characteristics.
mmWave — very high frequency, capable of extraordinary speeds, with severe limitations: range measured in hundreds of metres, and signals blocked by walls, foliage and rain. Deployed only in dense urban areas and venues.
What 5G genuinely improves beyond speed: much lower latency, which matters for responsiveness; and far higher device density, supporting many more connections in one area — the real benefit at crowded events, where 4G networks saturate.
Network slicing allows dedicated virtual networks with guaranteed characteristics, used for industrial and emergency services rather than consumers.
Wi-Fi calling (VoWiFi) routes voice calls over your broadband rather than the mobile network. The call still uses your normal number and your normal allowance — it is not an internet calling app.
Why it matters: it solves indoor coverage, which is the most common complaint about mobile service. Thick walls, basements, rural properties and modern insulated buildings with metallic coatings all attenuate mobile signal severely, and Wi-Fi calling bypasses the problem entirely.
Practical points: handover between Wi-Fi and mobile mid-call is not always seamless; it depends on your broadband being up, so it fails in a power cut; and emergency calls may not transmit location accurately, so a registered address is required.
Check it is enabled — it frequently is not by default.